Device for splitting diamond drill cores



Aug. 26, 1947. J DICKENSON I 2,426,344

' DEVICE FOR SPLITTING DIAMOND DRILL coREs Filed Au 15, 1945 PatentedAug. 26, 1947 DEVICE FOR SPLITTING DIAlVIOND DRILL CORES John G.Dickenson, Toronto, Ontario, Canada Application August 13, 1945, SerialNo. 610,596

6 Claims. 1

In the work of making mineral surveys and explorations diamond drillingperforms a very important role. Diamond drill cores are frequently sentto distant points for assay or for examination and it is important thata tangible record of the cores sent from the source should be kept andit is desirable to maintain a section of the core and for this purposeit is desirable to split the core samples longitudinally so that acomplete half section of a core may be retained while the other half maybe sent for examination and analysis.

The principal object of this invention is to provide a very simple andeffective tool by means of which the core sections may be readily splitlongitudinally.

The principal feature of the invention consists in the novelconstruction and arrangement of a bottom die presenting a longitudinalcutting or fracturing edge associated with means for holding the core inposition in contact with said cutting or splitting edge, a splittingtool being supported above the core in a supporting frame and such toolbeing freely reciprocable and adapted to be struck a sharp blow toeffect the splitting of the core.

In the accompanying drawings Figure 1 is a part elevation and partsectional view of my improved core-splitting device.

Figure 2 is a part vertical mid-section and part elevational view takenthrough the line 22 of Figure 1.

Figure 3 is a plan section of the adjusting wheel and centre spindletaken on the line 3-3 of Figure 1 showing the lock washer for holdingthe splitting tool spindle in its released position.

Figure 4 is a view similar to Figure 3 showing the lock washer in thelocking position.

Figure 5 is an enlarged perspective detail of the preferred form ofbottom die block.

In the construction of device herein shown an arched frame structure Iis mounted on a suitable base block 2 which is preferably formed of apiece of hard wood suitably oiled. This base block is formed with arectangular recess 3 therein in which the bottom die block 4 is seated.The die block 4 is preferably formed of a piece of hardened steel havinga longitudinal recess extending from end-to-end in the top thereof.

In the centre of the bottom of this recess is formed a wedge-shaped rib5, from the bottom of which upwardly sloping side walls 6 extend to theparallel walls I which are spaced apart a distance slightly greater thanthe diameter of the drill core to be split.

When the core 8 is placed within the block it rests centrally on theapex of the rib 5 and is held in a central position by the engaging sidewalls 1 and is thus supported in a position to receive an impact blowfrom the top which will tend to fracture the core longitudinally alongthe line of the apex of the rib 5.

The rib 5 may be advantageously formed of a bar of hardened steel orother suitable material which may be turned in its socket in the blockto present four separate cutting edges.

The upper arched portion of the frame I is provided with a centralthreaded orifice 9 in which is rotatably mounted a threaded bushing Inwhich is provided with a suitable hand wheel l! to enable the bushing tobe rotated to be moved quickly upwardly and downwardly.

The bushing II] is formed with a central cylindrical orifice l2 in whichis slidably mounted a shank l3 preferably formed with a rounded top.

Mounted on the lower end of the shank [3 or forming part thereof is anenlarged cylindrical portion M formed with a pair of longitudinalkeyways l5. These keyways are engaged by key extensions |6 of a boss I!extending downwardly from the arched frame below the threaded bushing.

The bottom end of the block [4 is formed with a central tongue I 8 andon this tongue is mounted the jaw-shaped portion l9 of a core splittingtool 2|], being secured in position by a suitable taper pin 2| or otherdevice.

The bottom V-shaped cutting edge 22 of the splitting tool is extendedlongitudinally to a length corresponding to the length of the block 4.This tool 20 is moved upwardly and downwardly by operating the handwheel II to rotate the bushing I0 in the threaded orifice 9 of theframe. By turning the hand wheel the splitting tool is raised to permitthe insertion of the core 8 into the block 4. The rotation of the handwheel is then reversed which lowers the splitting block downwardly untilits cutting edge engages the top of the core, which edge extends thefull length of the section of the core to be split.

When the splitting tool is thus positioned the rounded upper end of theshank l3 may be struck a sharp blow with a hammer, thus imparting animpact blow to the splitting edge 22 of the tool 20 and co-operatingwith the bevelled rib 5 in the block 4 the sharp impact causes a cleanfracture throughout the length of the piece of core placed in the block4.

The shank i3 is formed with an annular groove 23 arranged adjacent toits upper end and a flat disc washer 24, which is pivotally secured by apin 25 to the upper end of the bushing I0, may be swung into the groove23 when the splitting block 20 will have been raised by the hand of theoperator following the splitting operation. The rtation of the bushingthen raises the block out of position and holds it clear from the lowerblock so that the operator will not have to hold the splitting block inthe upward position.

Then when the bushing is rotated in the opposite direction it lowers thesplitting block as described.

When the tool has been brought into contact I with the next core to besplit the washer is swung on its pivot to a position to clear the groove23 in the shank, thus allowing the shank to move freely downward whenstruck by a hammer.

The device is very simple in its construction but it has been proved tobe very efiective in operation and enables an accurate splitting ofdiamond drill core sections so that a sample of each section may beretained while the other is used for examination purposes.

What I claim as my invention is:

l. A device for splitting diamond drill cores, comprising a base, ananvil block having a recess adapted to retain a length of said coremounted in said base, a longitudinal splitting ib arranged in the bottomof said recess, a frame mounted on said base extending over said anvilblock, a member slidably mounted in said frame, and a bevelledcore-splitting tool secured to said slidable memher.

2. A device as claimed in claim 1, in which the recess in said anvilblock is formed with substantially parallel longitudinal side walls andinwardly bevelled walls extending downwardly from the bottom of the sidewalls to the longitudinal splitting rib which is formed with bevelledwalls extending upwardly and meeting in a sharp apex.

3. A device as claimed in claim 1, in which the frame extending over theanvil base is provided with a threaded orifice, and a threaded bushingis rotatable in said orifice in which the slidable member is guided tobring the tool into contact with the core to be split in alignment withthe anvil member, means for locking said slidable member to the bushing,and means for rotating said bushing.

4. A device for splitting diamond drill cores, comprising an anvil baseadapted to hold a core section, a longitudinal splitting edge mounted insaid base, a frame extending over said base, a bushing rotatablythreaded in said frame, a shank slidable and non-rotatable in saidbushing and adapted to be temporarily secured therein for adjustment, asplitting block secured to said shank with its cutting edge parallelwith the cutting edge of the anvil, and a hand wheel secured to saidbushing to effect rotation thereof to bring the cutting edge of saidsplitting block into engagement with said core section.

5. A device as claimed in claim 4, in which the slidable shank is formedwith longitudinal slidable guides to prevent the shank from turning whenbeing reciprocated in said bushing.

6. A device as claimed in claim 4, in which the slidable shank isprovided with an annular groove and a washer is pivotally mounted on theend of the bushing to be moved into and out of engagement with thegroove in said shank.

JOHN G. DICKENSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 205,989 Andrews July 16, 1878FOREIGN PATENTS Number Country Date 756,210 France Sept. 18, 1933

